Andrew Lipovsky/NBC(NEW YORK) — Jennifer Lopez dropped by The Tonight Show on Tuesday to talk about her new movie, Hustlers, opening nationwide on Friday, and told host Jimmy Fallon how she got Cardi B to appear in the movie.

The film, which follows strippers who fleece Wall Street high rollers, required Lopez to learn how to pole dance, which wasn’t easy, even for an experienced dancer like herself.

“It’s like acrobats, it’s like learning gymnastics or something you know, but with a pole, it was super hard, Lopez told Fallon.

That’s when J-Lo got the idea to ask former exotic dancer Cardi for a few pointers, and ultimately convinced the rapper to co-star in the film. “I said, ‘you have to be in this movie. You know this world. You know this world, you could teach us.'”

“I’m learning how to pole dance. I said, ‘It is really hard, this is really hard,’ J-Lo recalls telling Cardi. “She said, ‘Oh yeah, it took me years, years to master.’ She goes, ‘But now I’m great at it.’ And I was like, “Well, then you have to be in the movie,” and she was like, “‘Absolutely.'”